Module 6-Overview of the Nervous System and Sense Organs Flashcards
What composes the central nervous system (CNS)?
The central nervous system consists of the brain and spinal cord
What composes the peripheral nervous system (PNS)?
The peripheral nervous system consists of a vast network of nerves throughout the body
What is the role of Oligodendrocytes?
Oligodencrytes: form myelin sheath in the brain and spinal cord
What is the role of ependymal cells?
Ependymal cell- lines the spinal cord and cavities of the brain;
What is the role of microglia:
Microglia- performs phagacytosis, surrounds microorganisms and cellular debris
What is the role of astrocytes?
Astrocytes extends through brain tissue; nourishes neurons, help form brain barrier and attaches neurons to blood vessels and provides structural support
What is the role of Schwann cells?
Schwann cells- forms myelin sheath around nerves in pns
What is the blood brain barrier (BBB) composed of?
Blood-brain and barrier is made from astrocytes and endothelial cells
What is the role of the BBB?
It allows small molecules to come in the brain or diffuse to the brain but it blocks larger molecules. It helps protect the brain from foreign substances.
What does sensory neurons do?
Sensory neurons detect stimuli or it detects something like touch, pressure, heat, cold etc and then it gives the information to the CNS
What does motor neurons do?
Motor neurons are responsible for carrying out the actions instructed by the brain and spinal
cord
What does interneurons do?
Interneurons- the decide what to do next afer receiving information and it determines what the action should be. After that, they give the instructions to the motor neurons.
Where are schwann cells found?
Swhann cells are found in the peripheral nervous system and they wrap themselves around the axon
What is the role of the neurilemma?
Neurilemma is essential for an injured nerve to regenerate or grow back
Where are oligodendrocytes found?
The oligendrocytes is found in a myelin sheath.
What are the parts of a neuron?
Cell Body ( Soma), Dendrites, axon and axon terminal
What does the Cell Body ( Soma) do?
It contains the nucleus, which holds the neuron’s genetic information, and other organelles that keep the neuron alive and functioning.
What does the dendrites do?
They receive messages from other neurons and transmit those messages to the cell body.
What does the axon do?
responsible for carrying a signal from one end of the neuron to another
What doe the axon terminal do?
These terminals release chemicals called neurotransmitters, which communicate with the next neuron in the chain.
What is a synapse?
is how neurons communicate with each other. Its like where one neuron passes information to another neuron
What is the role of the medulla oblongata?
The medulla oblongata helps regulate breathing, helps regulate the heart rate, controls the blood vessel diameter etc
What are the parts of the brainstem?
The parts of the brainstem is the midbrain, the pons, and medulla oblongata
What is the role of the cerebellum?
The cerebellum receives, processes messages from all over the brain. It controls balance, movement, and coordination. It stores information necessary for muscle groups to work together to perform smooth, efficient and coordinated movements
What is the cerebrum?
The cerebrum is the largest portion of the brain. It is where we have the ability to think, remember, feel, use judgement etc.
What is the role of the frontal lobe?
Frontal lobe- responsible for reasoning, planning, problem solving etc
What is the role of the parietal lobe?
Parietal lobe- responsible for touch
What is the role of the occipital lobe?
Occiptial lobe- responsible for vision
What is the role of the temporal lobe?
Temporal lobe- responsible for hearing
What is the role of the insula?
The insula helps with our emotions and helps us understand
What is the difference between grey matter and white matter?
Grey matter does the thinking and processing, while white matter helps the brain’s messages travel quickly and efficiently to where they need to go.
What is the role of the sympathetic nervous system?
The sympathetic nervous prepares the body for physical activity. It is from the thoracic and lumbar regions of the spinal cord. It is flight or flight when we are in danger.
What is the role of the parasympathetic nervous system? What does a parasympathetic
response look like?
The parasympathetic system helps calm the body down. “Rest and digest
What are the types of sensory receptors and what type of stimulus does each detect?
Chemoreceptors- taste, smell, oxygen etc
Mechanorecptors- pressure, stretch, vibration
Thermorecptors- changes in temperature
Nocieoceptors- pain, tissue damage
Photorecptors- light ( only in eyes)
Proprioceptors- body movement and position
Why does white mater appear white?
The abundance of myelin
The division of the nervous system that carries information away from the central nervous system is?
Motor division
The sturcture that allows communication between the right and left hemispheres of the brain is the
Corpus callosum
This type of Nervous System cell forms the blood brain barrier
astrocytes
What kind of nerve cells are thought to be helpers for the neurons?
Glial Cells
What is the Autonomic Nervous system?
Controls involuntary bodily functions such as breathing and the heart beating
What is the Somatic nervous system?
Controls bodily voluntary functions
What type of glial cell secretes and helps circulate cerebral spinal fluid?
Ependymal cells
What is another term for nerve impulse?
Action Potential
The effect produced by a neurotransmitter is ultimately determined by:
Type of receptor
Type of neurons that send impulses allowing you to withdraw your hand when you touch hot object
Efferent neurons
This cranial nerve senses taste and controls facial expressions
facial
Visceral reflexes are controlled by
the autonomic nervous system
When a neuron is stimulated, which type of ion rushes into the neuron?
sodium
This cranial nerve controls many functions in the body including the heart, digestive system and lungs
vagus
Why can’t a neuron be stimulated during the refractory period?
because there is more Na+ inside the neuron and more K+ outside
Which is the innermost menige of the brain
pia mater
Neurons with alpha-adrenergic receptors are
excited by norepinephrine
This part of the limbic system is responsible for storing and recalling emotion
amygdala
White matter in the spinal cord is made up of
myelinated bundles of axons
This part of the diencephalon contains the centers for thirst, hunger and temperature control.
the hypothalamus
Spinal nerves are made up of
mixed fibres (sensory and motor neurons)
Decussation means that
the right side of the brain controls the left side of the body
At rest the membrane of a neuron is
polarized
Ascending tracts in the spinal cord carry which type of information
sensory signals to the brain
This division of the nervous system has long preganglionic neurons and short postganglionic neurons. It primarily uses the neurotransmitter acetylcholine
parasympathetic division
Which nerve plexus innervates the head, neck and shoulders?
cervical plexus
The primary somatic motor area of the brain is located in which lobe?
Frontal lobe
What glands are found in the brain?
pituitary, hypothalamus, pineal
What happens to a neuron when it is depolarized?
Sodium rushes into the neuron. The inside becomes positively charges.
What is the function of descending spinal tracts?
To carry motor impulses from the CNS down the spinal cord to the effector (muscles)
What structures make up the diencephalon?
Thalamus, hypothalamus
